S10, pumping and popping sound when turning volume up from 0

Hi. I was using the S10 now for around 3 years on a 2.1 system feeding the subwoofer am, where the signal gets distributed to the satellites. This was working fine for me (damn single Bluetooth connection feature besides).

But now apparently it is not working anymore in the Wifi mode. As soon as I turn up the volume higher than 0, it produces a pumping and popping sound, so that my subwoofer strokes to the maximum back and forth with around 2 Hz. I immediately turned it off to not crash my woofer.

I took away the power and rebooted it once and had the same issue again. I didn’t try any other connection modes because I didn’t want to crash my speakers.

It sounds like a hardware problem to me.

Any advice? Are you familiar with such reports?
Greetings from Germany

Now I checked the device with some headphones in the AuxOut. It also appears when switching to Bluetooth. The signal is completely distorted…
So it looks my device died.

btw. is there any reason why the device is currently on offer for 69$ on the arylic store, but on the arylic store on Amazon it is 119€?